Plastic closure-receiver for metal container

ABSTRACT

A plastic receiver is internally threaded for reception of a plug. The receiver is provided with a radially extending flange with a downwardly opening channel on the underside thereof, an interior cylindrical wall of the channel serving as a back up face for a back up ring of an installation die, precluding collapse of the flange upon die forming of a retaining pocket of a metal container member upon flange installation. Circularly spaced irregularities provided on the upper outer surface of the flange effect matching deformations of the metal during installation, precluding subsequent rotation of the flange in the metal.

United States Patent 11 1 Bauman PLASTIC CLOSURE-RECEIVER FOR METAL CONTAINER [75] Inventor: George F. Bauman, Auburn, Ind.

[73] Assignee: Rieke Corporation, Auburn, 1nd. 221 Filed: May 5, 1972 [2]] App]. No.: 250,840

Related US. Application Data [63] Continuation of Ser. No. 25,031, April 2, 1970,

1451 Ju1y24,1973

Primary Examiner- -Thomas F. Callaghan Attorney-Joseph A. Naughton, Jr.

abandoned. ABSTRACT A plastic receiver is internally threaded for reception [52] U.S. Cl. 285/202, 220/39 R of a plug h receiver is provided with a radially [51] Int. Cl. F161 41/00 Ending flange with a downwardly opening channel on [58] held of Search 285/2031 the underside thereof, an interior cylindrical wall of the 285/201; 220/39 R channel serving as a back up face for a back up ring of 1 an installation die, precluding collapse of the flange I References-cued upon die forming of a retaining pocket of a metal con- UNITED STATES PATENTS tainer member upon flange installation. Circularly 1,851,938 3/1932 Rieke 285/203 Spaced irregularities provided on the pp Outer 1,961,712 6/1934 Schwartz.... 285/203 face of the flange effect matching deformations of the 2,144,346 1/1939 Schwartz... 285/203 metal during installation, precluding subsequent rota- 2,772,0l7 11/1956 Rieke 285/203 X tion of the flange, in the meta]. 2,916,311 12/1959 Keplinger... 285/202 3,179,280 4/1965 Littlefield...'. 220/39 R X 7 Claims, 7 Drawing Figures 40 Z8 K M 27 1/ 45 2/ 1 26 22 PATENIEDJUL24'975 3. 747. 962

' sum 2 or 2 Pi g1 INVENTOR GEORGE BAUMAA/ BY v AT TORN EYS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to closures for metal containers, and more particularly to a plastic receiver for a closure plug, and a method of insertion of the receiver in the metal for secure sealed retention therein without destruction thereof.

2. Description of the Prior Art For steel drums, internally threaded steel flanges are typically provided to receive externally threaded steel plugs. The flanges are installed in presses deforming the metal of a flange receiving pocket around the flange in such manner as to retain it and seal it.

It is desirable to provide a closure and receiver therefor which are of materials immune to container contents which might be corrosive to steel and other metals. Suitable means have been devised for appropriately lining the containers themselves, but problems have been countered in efforts to provide closure receivers which can be readily installed with more-or-less conventional equipment without damage to the receiver. Many plastics have the desired immunity to container contents, but do not have strength sufficient to enable conventional tooling to form the metal around the flange without collapsing the plastic.

SUMMARY Described briefly, according to a typical embodiment of the present invention, a plug receiver is provided with a radially extending flange for reception in a formed pocket of a metal container component, with the flange having appropriate back up surfaces and the die employed having appropriate back up faces in engagement therewith to avoid deformation and collapse of the receiver as the pocket is die formed into interlocking sealing engagement therewith to securely mount the receiver in the metal. The receiver may have an irregular configuration on the metal engaging surfaces thereof to effect a matching irregularity in the metal and preclude rotation of the receiver, once installed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of a metal container lid having a partially pre-formed pocket therein for reception of a closure assembly.

FIG. 2 is an enlarged fragmentary section taken at line 2-2 in FIG. 1 and viewed in the direction of the arrows.

FIG. 3 is a plan view of the closure receiver employed according to a typical embodiment.

FIG. 4 is a s'ectiontaken at the same location as line 2--2 but with the receiver securely mounted in the metal container wall.

FIG. 5 is a top-plan view of a completed assembly with the closure plug installed in the receiver.

FIG. 6 is an enlarged fragmentary section taken on a plane containing the axis of the assembly and illustrating the position of the die parts at the end of the forming operation effected during installation.

FIG. '7 is a fragmentary top plan view of a partially preformed pocket incorporating indentations therein formed prior to closure installation.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. ll, there is shown the end 11 of a cylindrical container, with a partially pre-formed pocket 12 having aperture 13 in the center thereof. The inner surface of the metal is lined with some comparatively inert lining material as better shown at 14, for example in FIGS. 2 and 4. This lining can be merely a coating if desired. It should be understood, of course, that the invention can be practiced with unlined metal containers of shapes other than cylindrical.

The closure receiver 16 illustrated in FIG. 3 is circular in shape and has a plurality of irregularities on the periphery thereof in the form of circularly spaced depressions or indentations, preferably vertical grooves 17. As is shown in FIG. 4 and better shown in FIG. 6, the outer periphery 18 of the receiver flange has a rounded nose portion 19 of convex curvature with a lower marginal portion having a concave curvature 21, and a downwardly and inwardly inclined portion therebetween, thus providing a generally S-shaped cross section. It is not essential that (prior to assembly) the portion 12 be rounded just as shown in FIG. 6. Whatever the initial shape may be, it is likely to become rounded as shown during assembly, due to the forces involved in assembly. A downwardly opening channel 22 is provided with the inner wall 23 thereof being the exterior cylindrical surface of the cylindrical portion of the receiver, the interior of which is internally threaded at 24. The outer wall of the illustrated channel is an inner cylindrical surface 26, and the roof of the channel is a comparatively flat surface 27. The dotted line 28 in FIG. 6 represents an example of a suitable depth for the grooves 17. In FIG. 4, where the cutting plane of the section passes through one of the grooves to the right of center, the matching of the identation by the metal of the container member at 29 is illustrated.

For installation, and considering the embodiment of FIGS. 1, 2 and 3, along with the illustration in FIG. 6, the metal member 11 is placed on the supporting face 31 of the bottom die, with the receiver 16 having its cylindrical portion received in the central aperture wall 32 of the bottom die 33. The receiver is supported by .engagement of the lower face 34 of the flange thereof with the upper face 36 of the bottom die. The inner wall 26 of the flange is abuttingly engaged with the outer cylindrical wall 37 of the concentric ring 38 of the bottom die.

The top die 39 has a lower face 41 engaging the upper face 42 of the pocket 12. A center post 43 of the top die is received internally of the threads 24 and concentric therewith. A plurality of circularly arranged collets (collet 44 being shown in FIG. 6) is provided around the pocket. Each of these has a nose portion 46 for engagement with the outer surface of the wall of the pocket, the inner back-up wall 26 of the receiver being in horizontal alignment with the innermost surface of the nose portion 46 whereby the back-up ring 38 of the bottom die can provide direct straight-line support around the complete circumference of the flange.

In making the assembly, the receiver is locked into place as it is supported thoroughly. The top die confines it on top, while the bottom die supports the bottom, and the upwardly extending concentric ring of the bottom die provides lateral support at the inside wall 26 of the flange as the crimping jaws or collets draw the metal into the concave portion of the flange. With the receiver thus supported as the top part of the die or tool comes down toward the bottom die or tool at the same time the collets or jaws move radially inward, the premolded or otherwise formed serrations or indentations on the outer periphery of the closure receiver form the metal to the approximate shape of their form. This forming operation provides an inherent locking feature to the combination. The upwardly extending concentric ring on the bottom die or tool provides the rigid back up force needed to prevent collapse of the flange as the confining pressure around the circumference exerted by the collets as and when the tool or die has been closed, is exerted on the plastic. The center 40 of the curvature of the convex curve of the nose portion is above the level of the roof 27 of the channel, and the radius is small enough that the center 45 of the concave surface 21 of the flange need not be too far below the level of the roof 27 of the channel. Therefore the back up surface (the inner cylindrical wall) 26 of the channel is the illustrated embodiment) need not extend inconveniently far below the top 50 of the flange. Upon withdrawal of the collets and the top die, the assembly can be removed and an appropriate threaded plug can be inserted to complete the closure as shown in FIG. 5.

Advantages of the present invention include the fact that conventional existing available tooling for collettype clinching die or fixture operations, can be employed with only very slight modifications of the dies as indicated, for example, in FIG. 6. Existing tooling is thus adapted to installation of closure receivers and assemblies which can be made of various types of plastic, and possibly other materials, depending upon the medium to be shipped in the container. Because of the present invention, this can be accomplished without collapse of the receiver, thus assuring that a closure plug can be properly inserted and removed as desired. The receiver is secured in such manner as to avoid turning in the metal when the plug is screwed into or out of the receiver. Furthermore, the installation can be completed in a manner such that the assembly of the receiver to the metal is leak proof and all raw edges of the container metal are exterior to the combination and isolated from container contents.

In some instances the type of material employed in the closure is too soft to form sufficient indentations or otherwise irregular shapes into the metal to obtain a good anti-rotation lock. In such instances, therefore, it may be necessary in the initial draw forming the pocket that there be serrations or other irregularities included. An example is illustrated in FIG. 7 wherein the circularly spaced indentations 51 are provided in the pocket during the initial draw and prior to assembly of the closure receiver thereto.

In the illustrated embodiments, the aperture, pocket, and closure assembly is circular. It is conceivable that closures of non-circular configuration could be advantageous in some instances, and the features of the present invention could be incorporated in non-circular closures, and installation thereof. Also it has been mentioned that irregular shapes other than indentations or serrations might be used on the flange to provide the anti-rotation lock. Many such possibilities come to mind and include oval, hexagon, and lugs, to mention but a few. The lining material may incorporate a pressure sensitive sealing feature or may have a sealant added to it in the pocket area. Even without the provision of a special sealing feature either in the pocket or on the flange, the fit and retention attainable according to the present invention can be adequate for sealing purposes.

What is claimed is:

1. The combination comprising:

a metal container having a flat wall with a hole extending through said wall and a collar around said hole, said collar having a first portion extending away from said wall and a second portion connected to said first portion and extending parallel with said wall toward the center of said hole;

a plastic cylinder having a hollow center and internal threads extending around said center for receipt of a threaded, plug, said cylinder having a second end within said container and a first end adjacent said collar; and, circular plastic flange integrally connected to said first end and including a first continuous wall extending radially outward from said cylinder and a second continuous wall of constant length perpendicularly connected to said first wall and extending axially with, but spaced from, said cylinder towards said second end defining a continuous channel between said second wall and said cylinder, said channel having a pair of parallel side surfaces, said flange having an outer rounded corner protruding outwardly of said first wall and said second wall; and wherein, said flange is mounted to said collar which conformingly fits externally against said flange including said rounded corner of said flange, said first portion and said second portion abut externally against respectively said second wall and said first wall said collar having a concave shape in said first portion with a center of concave curvature located outwardly of said collar and between said first wall of said flange and the distal end of said second wall, said collar having a convex shape to receive said rounded corner with a center of convex curvature located inwardly of said collar and between the opposite sides of said first wall, said collar snuggedly engaging and conforming to convex and concave surfaces of said rounded corner, at least one of said collar and said comer having anti-rotation means cooperating to prevent rotation of said flange with respect to said collar.

2. The combination of claim 1 wherein: said first wall of said flange includes a continuous circular ledge which receives said second portion of said collar with said rounded corner of said flange gripped between said first portion and said second portion.

3. The combination of claim 2 wherein: said rounded corner is interrupted by grooves in said flange which extend axially with said cylinder; and, said second wall has an inner cylindrical surface concentric with and facing said cylinder, said second wall has an outer surface with irregular surface features thereon with said collar conforming thereto precluding rotation of said flange in said collar.

4. The combination of claim 3 wherein:

said grooves each include a flat surface extending axially along said cylinder and through said rounded corner.

said collar has an S-shaped cross section formed by said second portion, said convex curvature and said concave curvature.

7. The combination of claim 6 wherein:

said rounded corner defines a discontinuous cylindrical surface concentric with a discontinuous cylindrical surface defined by said grooves and concentric with said cylinder.

UNITED STATES PATENT OFFICE H CERTIFICATE CORRECTION Patent bio, 3,74Z7,96Z D d July 24, 197 3 Inventor-(sf George F. Bauman 'It is certi fied that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 9, for "pocket 12'' read "pocket or collar 12'';

Column 4, line 61 and following, for "said second wall has an outer surface with irregular surface features thereon with said collar conforming thereto" read "said collar conforming to said grooves and".

Column 4, line 67, for "along" read "with".

Column 5, line 4, for "flexibility of" read "back up surface on".

Signed and sealed this 21st day of January 1975.

(SEAL) Attest:

McCOY M. GIBSON JR. C. vMARSHALL DANN Attesting Officer Commissioner of Patents FORM PO-105O (10-69) USCOMM-DC 60376-P69 w 0.5. GOVERNMENT PRINTING orrlce Isis o3sess4. 

1. The combination comprising: a metal container having a flat wall with a hole extending through said wall and a collar around said hole, said collar having a first portion extending away from said wall and a second portion connected to said first portion and extending parallel with said wall toward the center of said hole; a plastic cylinder having a hollow center and internal threads extending around said center for receipt of a threaded plug, said cylinder having a second end within said container and a first end adjacent said collar; and, a circular plastic flange integrally connected to said first end and including a first continuous wall extending radially outward from said cylinder and a second continuous wall of constant length perpendicularly connected to said first wall and extending axially with, but spaced from, said cylinder towards said second end defining a continuous channel between said second wall and said cylinder, said channel having a pair of parallel side surfaces, said flange having an outer rounded corner protruding outwardly of said first wall and said second wall; and wherein, said flange is mounted to said collar which conformingly fits externally against said flange including said rounded corner of said flange, said first portion and said second portion abut externally against respectively said second wall and said first wall said collar having a concave shape in said first portion with a center of concave curvature located outwardly of said collar and between said first wall of said flange and the distal end of said second wall, said collar having a convex shape to receive said rounded corner with a center of convex curvature located inwardly of said collar and between the opposite sides of said first wall, said collar snuggedly engaging and conforming to convex and concave surfaces of said rounded corner, at least one of said collar and said corner having anti-rotation means cooperating to prevent rotation of said flange with respect to said collar.
 2. The combination of claim 1 wherein: said first wall of said flange includes a continuous circular ledge which receives said second portion of said collar with said rounded corner of said flange gripped between said first portion and said second portion.
 3. The combination of claim 2 wherein: said rounded corner is interrupted by grooves in said flange which extend axially with said cylinder; and, said second wall has an inner cylindrical surface concentric with and facing said cylinder, said second wall has an outer surface with irregular surface features thereon with said collar conforming thereto precluding rotation of said flange in said collar.
 4. The combination of claim 3 wherein: said grooves each include a flat surface extending axially along said cylinder and through said rounded corner.
 5. The combination of claim 4 wherein: said channel extends to a location between said center of concave curvature and said center of convex curvature providing flexibility of said second wall to allow said collar to conformingly fit against said second wall without fracturing said second wall.
 6. The combination of claim 5 wherein: the upper face of said flange is sealingly engaged with said second portion; and, said collar has an S-shaped cross section formed by said second portion, said convex curvature and said concave curvature.
 7. The combination of claim 6 wherein: said rounded corner defines a discontinuous cylindrical surface concentric with a discontinuous cylindrical surface defined by said grooves and concentric with said cylinder. 